Now, in the root directory of this project, I run "thin start", and it works. This is just a small project and would only run in my local machine. So I need not to use Nginx and I plan just to use "thin".

Well, the applcation should run automatically when the server starts. How could I accomplish this?

I have run:

sudo thin install
sudo update-rc.d -f thin defaults

And it seemed that thin could run automatically However, where could I config this to run my application?

Eh....Maybe this question have nothing to do with sinatra or thin. I just need something automatically run when the machine starts. I'm not familiar with Linux o(////)o